This invention relates generally to heavy duty plastic bags made from single or multi-ply polyolefin materials, such as LD, HD, and LLD polyethylene and polypropylene, as well as other woven or nonwoven, synthetic or non-synthetic materials. Such bags are typically used to package materials such as fiberglass insulation, salt, potting soil, small landscaping rocks, pet food and similar heavy materials. While the invention has particular application to bags with a capacity of from 20 to 100 pounds, the principle of the invention is applicable to bags of any size.
Conventional, heavy-duty bags of the prior art are typically cut along the top with a knife or other suitable tool to define a sufficiently large opening through which the contents of the bag are dispensed. In the absence of a cutting knife or tool, attempts to manually tear open the bag by hand are often futile, because of the relative thickness and durability of such bags. Once opened, the bag must generally be embraced with both arms, lifted and inverted to dispense the contents from an opening in or near the top of the bag. In many cases, this requires substantial physical effort, and sometimes results in inadvertent uncontrolled dumping or over-dumping of the contents.
Applicant""s prior issued U.S. Pat. No. 5,593,229 describes a heavy duty bag with an easily-removable corner adapted for being hand-torn to form a hole for pouring contents from the bag. The preferred embodiments of the bag described in the ""229 Patent include a perforated vertical tear line extending downwardly from a top end edge of the bag to a second tear line extending from the first tear line towards the near side edge of the bag. While this bag solved many problems of the prior art, certain disadvantages and limitations still existed. Principally, the corner of the bag remained relatively difficult to tear by hand at the junction of the first and second tear lines in the case of a diagonally extending second tear line, and along the entire length of the second tear line in the case an arcuate line. Where the second tear line extended diagonally towards the near side edge of the bag, the difficulty in tearing resulted from the lack of a smooth transition from the first tear line to the second tear line. The bag with the arcuate second tear line provided a better transition from the vertical first tear line, but required greater effort to remove the torn corner due to the formation of perforations directly against the machine direction of the bag.
Therefore, it is an object of the invention to provide a bag with an improved easy-open corner portion.
It is another object of the invention to provide a bag with a perforated tear line including one or more arcuate transition segments to facilitate tearing the bag along a predetermined path.
It is another object of the invention to provide a bag with a perforated tear line which includes relatively few perforations formed against, or generally perpendicular to, the machine direction of the bag; the xe2x80x9cmachine directionxe2x80x9d being a direction extending longitudinally from one end edge of the bag to the other.
These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing an improved bag including first and second polyolefin walls with a thickness of between 3 and 12 mils. The bag has joined opposing side edges, opposing end edges, and at least one seal line proximate one of the end edges. The seal line extends laterally from one side edge to the other for sealing closed an end of the bag. The improvement in the bag is a perforated tear line defining an easy-open corner portion of the bag removable to form a pourer. The perforated tear line includes a vertical segment defined by a series of closely spaced perforations formed in the first and second walls of the bag and closer to one side edge of the bag than the other. The vertical segment extends in a straight path outwardly from the seal line and generally parallel the closer side edge of the bag. An arcuate transition segment of perforations begins at an end of the vertical segment and extends in an arcuate path towards the closer side edge of the bag. A diagonal segment of perforations extends along a straight incline from an end of the arcuate transition segment towards the closer side edge of the bag. The vertical segment, arcuate transition segment, and diagonal segment cooperate to enable the corner portion of the bag to be torn in a progressive tearing motion to form a hole in the bag from which the contents can be poured.
According to another preferred embodiment of the invention, the perforations of the tear line are between {fraction (1/16)}th inch and xe2x85x9cth inch long.
According to another preferred embodiment of the invention, the perforations of the tear line are between {fraction (1/16)}th inch and xe2x85x9cth inch apart from adjacent perforations.
According to another preferred embodiment of the invention, the arcuate transition segment of the tear line is less than 20 percent of the overall length of the tear line.
According to another preferred embodiment of the invention, the arcuate transition segment of the tear line defines a radius of approximately 2 inches.
According to another preferred embodiment of the invention, the diagonal segment of the tear line extends from the arcuate transition segment at an angle less than 60 degrees to the closer side edge of the bag.
According to another preferred embodiment of the invention, the diagonal segment of the tear line extends from the arcuate transition segment at a 45 degree angle to the closer side edge of the bag.
According to another preferred embodiment of the invention, the tear line has a second arcuate transition segment of perforations beginning at an end of the diagonal segment and extending in an arcuate path towards the closer side edge of the bag.
According to another preferred embodiment of the invention, the tear line has a horizontal segment of perforations beginning at an end of the second arcuate transition segment and extending in an arcuate path towards the closer side edge of the bag.
According to another preferred embodiment of the invention, the first and second arcuate transition segments of the tear line each define a radius of approximately 1 inch.
According to another preferred embodiment of the invention, a second seal line is spaced-apart from the first seal line and extends laterally from one side edge of the bag to the other. A handle is formed in an area between the two spaced-apart seal lines.
According to another preferred embodiment of the invention, the handle is a generally U-shaped, die-cut slit.